The present invention relates to a combustion chamber.
More especially, the invention relates to a combustion chamber which is particularly well suited for--although not restricted to--use in refuse incinerators.
Special problems exist in the operation of refuse incinerators, because the refuse mix tends to produce combustion products which form slag deposits on the inner wall of the combustion chamber. When this occurs, quite substantial difficulties result in terms of further operation of the incinerator. To overcome this problem it is known to make the inner wall of the combustion chamber--which is spaced with clearance from the gas-tight outer wall--of plates having or defining openings through which air can be passed from the clearance into the combustion chamber. This air prevents the settling of deposition-forming matter on the plates and the problem is thus overcome. However, the prior art is still possessed of difficulties which have heretofore not been solved.
An incinerator is known from German Allowed Application DE-AS No. 2,317,064 in which the plates are of metal and define air-outlet gaps with one another. A problem with this construction is the danger that--should the air supply to the outlet gaps suddenly fail--the metallic plates will corrode under the influence of the temperature prevailing in the combustion chamber, unless specially heat-resistant metal is used which, however, is then again very expensive. Also, metallic plates are relatively heavy and require a correspondingly massive supporting structure to sustain that weight.
Another proposal, made in VGB Kraftwerkstechnik 57 (1977), pp. 341-344, suggests the use of ceramic plates provided with air-outlet holes arranged in form of a grid or raster. These plates are then screwed or bolted to the outer combustion-chamber wall. They are, however, also relatively heavy and quite expensive in terms of manufacture and installation.